Abstract. Rivers often become primary receivers of pollution and this affects the ecological state of water biogeocenoses, soil and plants. Uneven water use in the upper and lower reaches of the Syrdarya River and accumulation of contaminants in the upper reaches leads to changes in the ecological balance in the middle reaches. Hydrochemical indicators of water samples from the Syrdarya River in the middle flow and suitability of water for irrigation were studied. Samples were taken during the warm period of the year from 8 stations during 2018 and 2019. The water was found to be slightly mineralised with a normal value of electrical conductivity. 18.75% of water samples had an alkaline reaction; in 97.9% of samples, the bicarbonathion content exceeded the standard values. By chloride content 95.84% of samples are suitable for surface irrigation. The concentration of nitration was within the limits of normative values. To be used for irrigation purposes, it is necessary to dilute river water with fresh water, normalise pH and regularly monitor hydrochemical indicators.